Effect of oleic acid on the stability and rheology of nanoaluminium/JP-10 bi-phase system

Aluminium (Al) nanoparticles absorbed by oleic acid (OA) were prepared to study the effect and mechanism of OA on the stability and rheology of a nanoAl/exo-tetrahydrodicyclopentadiene (JP-10) bi-phase system. The absorption layer was characterised by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and energy dispersive X-ray spectroscopy. The effect of OA on the stability and rheology of nanoAl/JP-10 suspensions was measured. Results show that OA reduces the surface tension of JP-10 and the contact angle between the two phases. The absorption of OA on the surface of the particles occurred through the reaction between the −COOH of OA the −OH of Al particles. The amount of absorption increased as the concentration of OA increased. Adding OA enhanced the stability of the nanoAl/JP-10 bi-phase systems by hindering particles aggregation. A suspension with 5.0% solid load demonstrated no clear layer separation 1 month after preparation with 1.0% OA. OA also reduced the viscosity of the systems. A 0.5% concentration of OA is best for a system with 20% solid load. The viscosity-reducing effect of OA was determined by its comparative amount, and the ratio of OA/Al should be above 2.5%.